This is a nice article by Callum Williams in the Economist, picking up on Ken Rogoff’s pitch for abolishing cash.  

For clarity, I wanted to distinguish my approach from Ken Rogoff’s.  I wrote in “Q&A: Apple Pay and the Future of Electronic Money" 

I think physical cash is likely to play a minor role for a long time after it has been mostly eclipsed by electronic payment. For example, I think the strong demand for anonymity for certain kinds of purchases will make it very hard to eliminate paper money entirely. (If we tried to abolish paper dollars entirely, people would start using paper euros or yen or pounds for the purchases they wanted to make anonymously.)

So it is important to make some provision for what happens with paper currency rather than just assuming it can be abolished.